You may consider me to be sprinting in a circle
Or helping you to navigate the alphabet
I might even be like a small explosion.
But you'll have to prove that you know me regardless.
What am I?
Sprinting could be by itself, the circle might be on the subject of something instead and it would still fit.
You don't have to navigate the alphabet very far.
It's more about the sound, really.
Think about another term for "proving that you have knowledge of something".
Consider that my favourite way of creating a puzzle is to use synonyms of things that relate to the subject indirectly: for example, for "leaves" I might say "If you want to be green, move away from the room." Think about synonyms for words I've used in each line, especially line 1.
Lines 1 and 3 refer to colloquial names for the object, rather than the object itself. Line 2 is about an idiom that describes what the object does. Line 4 refers to something you need to do in order to use one.